Guiding device, especially for splitting and beveling machines

ABSTRACT

A guiding device for splitting and beveling machines in which the material to be split or beveled is fed between a cutting member and a guiding element, said guiding device having a guiding part comprising at least a first guiding section forming the front guiding section when looking in the direction in which the material to be split or beveled is fed toward the cutting member and a second guiding section located behind the first guiding section when looking in the direction in which the material to be split or beveled is fed toward the cutting member. The arangement is such that the first guiding section is made of a synthetic material with a low coefficient of friction with regard to the material to be split or beveled, whereas the second guiding section is made of a hard metal.

United States Patent Fingerle et al.

GUIDING DEVICE, ESPECIALLY FOR SPLITTING AND BEVELING MACHINESInventors: Karl Fingerle, Korb; Jurgen l-laag,

Stuttgart-Hedelfingen, both of Germany Assignee: Fortuna-WerkeMaschinenfabrik Aktiengesellschaft, Stuttgart. Germany Filed: Sept. 11,1972 Appl. No.: 288,099

Foreign Application Priority Data Sept. 10, 1971 Germany ..P 21 45 US.Cl 83/4, 83/1, 83/422, 83/450 Int. Cl B26d 3/12 Field of Search 83/4, 1,422, 3, 83/450 References Cited UNlTED STATES PATENTS 10/1967 Braun 83/4X Primary ExaminerJ. M. Meister Attorney-Walter Becker [57] ABSTRACT Aguiding device for splitting and beveling machines in which the materialto be split or beveled is fed between a cutting member and a guidingelement, said guiding device having a guiding part comprising at least afirst guiding section forming the front guiding section when looking inthe direction in which the material to be split or beveled is fed towardthe cutting member and a second guiding section located behind the firstguiding section when looking in the direction in which the material tobe split or beveled is fed toward the cutting member. The arangement issuch that the first guiding section is made of a synthetic material witha low coefficient of friction with regard to the material to be split orbeveled, whereas the second guiding section is made of a hard metal.

9 Claims, 4 Drawing Figures GUIDING DEVICE, ESPECIALLY FOR SPLITTING ANDBEVELING MACHINES The present invention relates to a guiding device,especially for splitting and beveling machines, in which the material tobe machined carries out an advancing movement and is passed between acutting element and a guiding device which is located in a predeterminedspaced arrangement relative to the cutting element.

Splitting and beveling machines of the type involved preferably operatewith a rotating belt knife and are employed primarily for a laminardividing of soft foilshaped, band-shaped, or plateshaped materials, suchas leather, synthetic leather, rubber, and the like. Beveling machinesof the type here involved in general have a bell-shaped or circularslitting knife as cutting element and are employed primarily for theshaping of the edges of upper leather parts in the shoe industry, whichedges have a tapering cross section or end.

With all of the above mentioned machining operations there isencountered the problem of a precise guiding of the material to bemachined within the region of the cutting edge of the cutting element.To solve this problem, a guiding device is provided which is adjustableand spaceable from the cutting edge of the cutting element in conformitywith the respective requirements and the guiding surface of which withits distance from the cutting edge determines the thickness of thematerial which remains after the splitting or beveling and thusdetermines the complementary thickness of the chip cut off from theblank. Consequently, the precision of the thickness of the material andthe cross sectional shape of the material as obtained by the splittingand beveling depends to a major extent on the precise shape and thusalso on the wear resistance of the guiding surface of the guidingdevice. At the same time the requirement has to be met that the guidingsurface has a low frictional effect relative to the material which isunder a high pressure passing along the guiding surface becauseotherwise an unduly high braking and upsetting of the material willoccur which might even result in the stopping of the advancing movementand thus might cause an interruption of the operation. This applies inparticular to the customary feeding drives with a feeding element formedby a rotating friction roller or friction drum, which feeding elementengages that surface of the material which is opposite to the guidingsurface of the guiding device. In this connection, the friction betweenthe material and the guiding surface must be considerably less than thefriction between the material and the feeding element in order to assurea proper feeding or advance.

It is, therefore, an object of the present invention to provide aguiding device for the above referred to field of application which willmake it possible to obtain a high wear resistance and thus a highshaping precision of the guiding surface even after a long period ofoperation while simultaneously the frictional effect between materialand guiding surface is kept low.

This object and other objects and advantages of the invention willappear more clearly from the following specification in connection withthe accompanying drawings, in which:

FIG. 1 illustrates in cross section the working range of a beltknife-splitting machine with a guiding device according to theinvention.

FIG. 2 illustrates a cross sectionthrough a modified guiding deviceaccording to the invention for a belt knife-splitting machine.

FIG. 3 illustrates in cross section the working range of a bellknife-beveling machine with a guiding device according to the invention,said section being taken along the line Ill ll] of HO. 4.

FIG. 4 is a section taken along the line lV IV of FIG. 3.

The guiding device according to the present invention is characterizedprimarily in that the guiding surface of the guiding device comprises atleast two sections which, when viewed in feeding direction of thematerial to be processed, are located one behind the other. The guidingdevice according to the invention is furthermore characterized in thatthe first section representing the front section when viewing in feedingdirection consists of synthetic material with a low friction coefficientrelative to the material to be processed, whereas the second sectionwhich when viewing in feeding direction represents the rear sectionconsists of hard metal.

Numerous tests have shown that the combination of a guiding surfacesection consisting of slidable synthetic material with a guiding surfacesection consisting of hard metal in the above mentioned sequencerelative to the feeding direction furnishes excellent results as to themachining precision and a trouble-free operation. The guiding surfacesection which consists of slidable synthetic material absorbs aconsiderable portion of the pressing-on force exerted by the material,whereas the guiding surface section which consists of hard metal willassure a high precision of the splitting distance between the guidingsurface and the cutting edge and ,will further assure that only anegligibly slight yieldability occurs with regard to the pressing-onpressure of the material.

An advantageous further development of the invention relates to aguiding element for splitting and beveling machines with a rotatablefeed drive element which frictionally engages the surface of thematerial to be machined, and with a guiding element which engages theother surface of the material to be machined and acts as counter bearingfor the pressure exerted by the feed drive element, and with aknife-like cutting element. This further development is characterizedprimarily in that the first section of the guiding surface is arrangedwithin the region of the feed drive element, whereas the second sectionof the guiding surface is located within the range of the cutting edgeof the cutting element. In this way the pressure of the feed driveelement, for instance a friction roller or a friction drum, is limitedto the highly slidable guiding surface section which has a low friction,whereas the guiding surface section consisting of hard metal need toabsorb essentially only the remaining pressure between cutting elementand material while at the same time assuring a maximum machiningprecision.

The guiding device according to the present invention may be furtherimproved by designing that section of the guiding device which forms thesecond surface section as counter bearing supporting the syntheticmaterial of the first guiding surface section in a direction opposite tothe feeding direction of the material to be machined. This design makesit possible that also such materials may be employed'for the firstguiding surface section which wile having a low friction are frequentlyonly to a minor degree resistant to deformation, while the metallicguiding surface section, due to its supporting effect, will prevent ayielding and, with many particularly favorable synthetic materials, aflowing or creeping thereof in feeding direction under the influence ofthe material passing therethrough. For this purpose there will suffice awidth of the second guiding surface section which is considerablynarrower than the width of the first guiding surface section so that alarge pressing and engaging surface for a friction roller or the likewill be available with a minor braking only of the material on theguiding surface. In this connection, as mate rial for the first guidingsurface section there is preferably employed polytetrafluoroethylenewhich has excellent sliding and wear-resistant properties because theflow and creep tendency of this material as caused by the materialpassing therethrough is reduced by the supporting effect of the secondguiding surface section. For purposes of increasing the wear resistanceof the metallic guiding surface section, a surface hardening or a hardmetal reinforcement of the corresponding element of the guiding devicemay be provided.

Referring now to the drawings in detail, according to the device shownin FIG. 1, the foil-like material 1 to be split passes from a supportingtable 6 through a working gap between a friction roller 2 serving asfeed drive and provided with an elastic rubber mantle 7, on

the one hand, and the guiding surface 11, on the other hand, of astrip-like guiding element according to the invention. Within the endrange of the working gap there is provided the cutting edge 4 of acutting member in the form of a band knife 3 which rotates in adirection perpendicular to the drawing plane and which is mounted in theworking range of the machine in a customary knife guiding means 5 notillustrated in detail. The distance between the cutting edge 4 and theguiding surface 11 determines the thickness of the material portion 1aleaving the machine whereas the split off portion or chip lb leaves themachine below the beltknife 3. l

- The guiding surface 11, when viewing the material 1 in feedingdirection as indicated by the arrow A, consists of two guiding surfacesections 11a and 1 lb which are located one behind the other. Thesection 110 is located substantially within the range of the drivingsurface area of the friction roller 2, whereas the section 11b, islocated primarily within the range of the cutting edge 4 of the beltknife 3. The profile of the two guiding surface sections is shaped inconformity with the corresponding surface of the oppositely locatedmachine elements. More specifically, section 11 conforms in its startingor entrance portion to the surface of table 6 and subsequently to thecircumferential curvature of the friction roller 2, while the profilecurvature of the I guiding surface section 11b in its first partconforms to the end portion of the section Ila and subsequently followsthe inclination of the top side of the edge section of the belt knife 3.

The feeding of the material is effected by the friction roller 2rotating in the direction of the arrow B. The surface of friction roller2 is relatively strongly pressed against the material and engages thematerial within the range of the guiding surface section lla. Thispressure is absorbed by the guiding surface section 110 at a minimum offriction, the section 11a consisting of a relatively thin layer ofpolytetrafluoroethylene. in a direction counter to the feedingdirection, this layer of synthetic material is supported by the shoulderof the guiding surface section 11b so that no undue deformation in viewof the flow tendency of the synthetic material can occur. Together witha preceding guiding strip 8a and a following guiding strip 8b, theguiding device c is inserted into a holding strip and thus formstogether therewith a guiding strip in the form of a compact structuralunit which in customary non-illustrated manner is adjustably mounted onthe machine frame.

The guiding element according to the present invention may, inconformity with FIG. 2, also be composed of two separate parts 13 and 14which are interconnected by screws 12 so as to form a structural unit.This design in some instances yields advantages with regard to a precisemachining of the supporting surface for a layer 15 of synthetic materialrepresenting the guiding surface section of low friction as well as withregard to a precise machining of the section 16 (FIG. 2) of the guidingdevice representing the rigid guiding surface section. Moreover, in someinstances, this design facilitates the application of the layer ofsynthetic material.

If the metallic guiding surface section, especially according to FIG. 2,is not made of a hard material, it may expediently be subjected to asurface hardening, for instance, by chromizing, or by applying thereto ahard metal layer or a hard metal diffusion layer, or the like.

With the splitting machine according to FIGS. 3 and 4, a customary bellknife 103 with circular cutting edge 104 is provided as cutting element.Within the working range of the cutting edge 104 there is provided arotatable friction roller 102 which serves as feed drive for thematerial 1 to be split. The friction roller 102 is in customary manner(therefore not shown in detail) rotatably journalled for rotation aboutthe shaft 106 which extends in a direction transverse to the axis ofrotation 105 of the bell knife 103. The friction roller 102 is rotatedby a non-illustrated power drive in the direction of the arrow C.Moreover, the friction roller or the mounting therefor is arranged so asto yield in a direction transverse to its axis of rotation and isresiliently pressed against a non-illustrated abutment in the directionof the arrow D toward the cutting edge of the bell knife so as to bespaced from the cutting edge by a slight distance. Under the influenceof the material 101 passing through the device, the friction roller 102is thus able to escape downwardly, which means in a direction oppositeto the arrow D, and presses the material upwardly against a guidingdevice according to the invention in the form of a guiding foot 100. Theguiding device is in customary manner rigidly connected to the machineframe but is adjustable relative to the cutting edge 104. When viewingin feeding direction of the material 101 indicated by the arrow E, theguiding surface 111 is again composed of two sections lla and lllb.Section 111a is formed by a layer of polytetrafluoroethylene, whereasthe section 11b consists of hard metal and by its spacing from thecutting edge 104 determines the precise thickness of the processedmaterial strand 101a leaving the device. The guiding surface 111, whenviewing in the direction of the axis of rotation of the bell knife (FIG.4), is arranged with decreasing distance from the cutting edge 104 inconformity with the desired wedge shape of the edge profile of thematerial 101 to be produced. For absorbing the lateral force which inview of the bell knife rotating in the direction of the arrow F actsupon the material, the guiding device is provided with an extension 107which at the same time supports the layer of synthetic material of theguiding surface section 111a against this lateral force which acts inthe circumferential direction of the bell knife.

It is, of course, to be understood that the present invention is, by nomeans, limited to the specific showing in the drawings but alsocomprises any modifications within the scope of the appended claims.What we claim is:

1. In a splitting and beveling machine which comprises cutting meanswith a cutting edge for splitting foil-shaped and band-shaped andplate-shaped relatively soft material, supporting table means forsupporting the material to be conveyed to and to be split by saidcutting means, and conveying means interposed between said supportingtable means and said cutting means and operable to convey the materialto be split from said supporting table means to said cutting means, aguiding device which includes: a guiding member having a guiding portionextending in slightly spaced relationship to and along said supportingtable means and said conveying means and confining therewith the guidingpath for the material to be split, said guiding portion having at leasttwo guiding sections which when viewed in the conveying direction ofsaid conveying means are located one behind the other so that that oneof said two sections which is closes t to said supporting table meansforms the first guiding section and the other one of said two guidingsections forms the second guiding section, said first guiding sectionhaving a guiding surface formed by a synthetic material with a lowcoefficient of friction with regard to the material to be split, andsaid second guiding section having a guiding surface formed by a hardmetal.

2. An arrangement according to claim 1, in which said conveying meansincludes a rotatable friction roller.

3. An arrangement according to claim 1, in which said first guidingsection is located within the region of said conveying means whereassaid secon guiding section is arranged within the region of the cuttingedge of said cutting means.

4. An arrangement according to claim 1, in which said second guidingsection forms a counter bearing supporting said first guiding section soas to exert a counter force thereon in a direction counter to theconveying direction of said conveying means.

5. An arrangement according to claim 1, in which the extension of saidfirst guiding section measured in the conveying direction of saidconveying means amounts to a multiple of the extension of said secondguiding section measured in the conveying direction of said conveyingmeans.

6. An arrangement according to claim 1, in which the two guidingsections of said guiding portion are formed by two guiding elements, andin which connecting means are provided firmly connecting said twoguiding elements together.

7. An arrangement according to claim 1, in which said first guidingsection has at least that area thereof which is intended for guidingcontact with the material to be split made of polytetrafluoroethylene.

8. An arrangement according to claim 1, in which said second guidingsection has that surface thereof surface hardened which is intended forguiding contact with the material to be split.

9. An arrangement according to claim 1, in which said second guidingsection is provided with a hard metal reinforcement.

1. In a splitting and beveling machine which comprises cutting meanswith a cuttiNg edge for splitting foil-shaped and bandshaped andplate-shaped relatively soft material, supporting table means forsupporting the material to be conveyed to and to be split by saidcutting means, and conveying means interposed between said supportingtable means and said cutting means and operable to convey the materialto be split from said supporting table means to said cutting means, aguiding device which includes: a guiding member having a guiding portionextending in slightly spaced relationship to and along said supportingtable means and said conveying means and confining therewith the guidingpath for the material to be split, said guiding portion having at leasttwo guiding sections which when viewed in the conveying direction ofsaid conveying means are located one behind the other so that that oneof said two sections which is closes t to said supporting table meansforms the first guiding section and the other one of said two guidingsections forms the second guiding section, said first guiding sectionhaving a guiding surface formed by a synthetic material with a lowcoefficient of friction with regard to the material to be split, andsaid second guiding section having a guiding surface formed by a hardmetal.
 2. An arrangement according to claim 1, in which said conveyingmeans includes a rotatable friction roller.
 3. An arrangement accordingto claim 1, in which said first guiding section is located within theregion of said conveying means whereas said secon guiding section isarranged within the region of the cutting edge of said cutting means. 4.An arrangement according to claim 1, in which said second guidingsection forms a counter bearing supporting said first guiding section soas to exert a counter force thereon in a direction counter to theconveying direction of said conveying means.
 5. An arrangement accordingto claim 1, in which the extension of said first guiding sectionmeasured in the conveying direction of said conveying means amounts to amultiple of the extension of said second guiding section measured in theconveying direction of said conveying means.
 6. An arrangement accordingto claim 1, in which the two guiding sections of said guiding portionare formed by two guiding elements, and in which connecting means areprovided firmly connecting said two guiding elements together.
 7. Anarrangement according to claim 1, in which said first guiding sectionhas at least that area thereof which is intended for guiding contactwith the material to be split made of polytetrafluoroethylene.
 8. Anarrangement according to claim 1, in which said second guiding sectionhas that surface thereof surface hardened which is intended for guidingcontact with the material to be split.
 9. An arrangement according toclaim 1, in which said second guiding section is provided with a hardmetal reinforcement.